Tubing hanger assembly



Jam 1963 J. M. LEBEAUX ETAL 3,072,420

TUBING HANGER ASSEMBLY Filed Dec. 8, 1958 5 Sheets-$heet 1 FIE-1 51' 50' INVENTORS 62 ATTORNEY Jan. 8, 1963 J. M. LEBEAUX ETAL TUBING HANGER ASSEMBLY 5 Sheets-Sheet 2 Filed Dec. 8, 1958 INVENTORS JACOB M. LEBEAUX CARLOS E.BALLARD BY W ATTORNEY n- 1953 J. M. LEBEAUX ETAL 3,072,420

TUBING HANGER ASSEMBLY Filed Dec. 8, 1958 5 Sheets-Sheet 5 F'IE 5 mvzn'rons .mcoa u. LEBEAUX 64 I66 CARLOS s. BALLARD BY M 5, W.

ATTO R N EY Jan. 8, 1963 J. M. LEBEAUX ETAL 3,072,420

TUBING HANGER ASSEMBLY Filed Dec. 8, 1958 Sheets-Sheet 4 F'IE EI I95 I I @r WI \94- T g 193 1:2

F "I E E] -n F l I94 gr I 5 I93 INVENTORS JACOB M. LEBEAUX CARLOS E. BALLARD BY My,

ATTORNEY TUBING HANGER ASSEMBLY Filed Dec. 8, 1958 V F' IE III] 5 Sheets-Sheet 5 282 an zaz 304 307 fi 3 k 280 33 :ggg// IOT T I E 1 mvzn'rons JACOB M.LEBEAUX CARLOS E. BALLARD BY H ATTORNEY United States Patent Ofilice 3,972,420 Patented Jan. 8, 1963 3,072,420 TUBING HANGER ASSEMBLY Jacob M. Leheaux and Carlos E. Ballard, Houston, Tex, assignors, by mesne assignments, to FMQ Corporation, San Jose, (Ialifl, a corporation of Deiaware Filed Dec. 8, 1958, Ser. No. 778,688 2 Claims. (6!. 265-137) The present invention relates to tubing hanger assemblies for use in well installations. More specifically, the invention pertains to a hanger assembly for suspending one or more strings of tubing within a well.

An object of the present invention is to provide an improved tubing hanger assembly.

Another object of the invention is to provide tubing hanger apparatus of improved and simplified construction for suspending one or more strings of tubing within a well and under tension throughout its or their entire length, as the case might be.

Another object of the invention is to provide a multiple tubing hanger assembly which enables the suspension under tension of a plurality of strings of tubing within a well in side-by-side relation.

These and other objects and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a fragmentary vertical section through a tubing hanger assembly of the present invention.

FIG. 2 is a perspective of reduced size of the tubing hanger couplings of FIG. 1.

FIG. 3 is a reduced horizontal section taken along the lines 3-3 of FIG. 1.

FIG. 4 is a reduced horizontal section taken along the lines 4--4 of FIG. 1.

FIG. 5 is a vertical section through a modified form of the tubing hanger assembly of the invention.

FIG. 6 is a reduced horizontal section taken along the lines 6-6 of FIG. 5.

FIG. 7 is a reduced perspective of the tubing hanger couplings of FIG. 5.

FIG. 8 is an enlarged plan of one of the seating elements for the tubing hanger couplings of FIG. 5.

FIG. 9 is an enlarged vertical section taken along the lines 99 of FIG. 6.

FIG. 10 is a vertical section through another form of the tubing hanger of the present invention, the plane of section being indicated by the lines 10-10 of FIG. 11.

FIG. 11 is a reduced horizontal section taken along the lines 1111 of FIG. 10.

Referring to the drawings, and particularly to FIG. 1, the tubing hanger assembly of the invention comprises a tubing head it) adapted for placement at the upper end of a well casing (not shown). The tubing head 10 is of hollow cylindrical construction, and at its upper end is formed with a neck portion 11 which at its top merges with an annular flange 12. An axial bore 13 extends through the tubing head, which bore is enlarged at its upper end by a counterbore 14.

The counterbore 14 is formed with a frusto-conical seat 15 at its lower end, upon which is seated a sealing assembly 16. The latter is generally cylindrical in shape, and its walls bear tightly against the surfaces of the bore section. The member 16 is downwardly tapered at its lower end so as to fit upon the seat 15.

The sealing assembly 16 is in the form of a sandwich, having upper and lower plates 17 and 18, respectively, of suitable material, preferably metal, and a packing element 19 therebetween, of any suitable resiliently yieldable packing material.

The elements 17, 18 and 19 of the seal 16 are held together by four headed screws 20, 21, 22 and 23 (FIG. 4), each of which extends through aligned bores (not shown) in the elements 17, 18 and 19. Each of these bores in the lower element 18 is tapped and is engaged by threads on the lower end of the corresponding screw. Two vertical cylindrical bores 28 and 29 extend through the sealing assembly 16 in slightly spaced, side-by-side relation (FIGS. 1 and 4).

The flange 12 is provided with a circular series of holes 30 adapted to receive bolts 31 whereby a blowout preventer (not shown) can be secured in operative position upon the flange 12 before installation of tubing strings presently to be described, and whereby a flow controlling unit, or Christmas tree 32, can be mounted in operative position upon the flange 12 after the tubing strings have been installed and the blowout preventer removed. A seal ring 35 is compressed within a groove 36 in the flange 12 and in a registering groove 37 in the under surface of the unit 32 (or in a corresponding groove in the under surface of the blowout preventer, as the case might be),

For the purpose of suspending two strings of tubing from the tubing head 10, two tubing hanger couplings 5t) and 51 are maintained side-by-side within the bore 13 and counterbore 14 of the said tubing head. Since the hanger couplings 50 and 51 are identical in structure, only the coupling 50 will be here described in detail. The hanger coupling 50 (FIG. 2) comprises an upper tubular portion 52, and a lower semi-cylindrical flange portion 53 connected thereto. A bore 54 adapted to receive a conventional back pressure valve extends through the coupling. The outside dimensions of the flange 53 are such that the flange fits into one half of the bore 13 of the tubing head 10 so that the flange 53 and the corresponding flange of the hanger coupling 51 fit loosely into the bore 13 in side-by-side relation, with their flat sides 50 and 51', respectively, in parallel, spaced apart relation (FIGS. 1 and 3). The bore 54 of the hanger coupling 50 is threaded at its lower end 55 (FIG. 1), and is thereby adapted to receive the upper threaded end 56 of a tubing string 57 so as to connect the string 57 to the coupling 56 for support thereby. At its upper end 58, the bore 54 is threaded for the purpose of receiving a threaded tool (not shown) that is used for installation of the hanger coupling. Adjacent its upper end, the coupling 50 is formed with an external annular groove 59 within which is an O-ring seal 60.

Two substantially conical recesses or notches 61 and 62 (FIG. 3) are formed in the flange 53 at the intersection of the bottom surface of the flange 53 and the arcuate side wall thereof, these notches being spaced approximately apart and being spaced equally from the intersections of the fiat and arcuate side walls of the flange 53. The notches 61 and 62are adapted to receive the conical inner ends of radially extending alignment and support pins 63 and 64, respectively. The pin 63 is mounted in a tubular guide 65 rigid with and projecting radially from the tubing head 10, and the pin 64 is mounted in a similar guide 66. Identical alignment and support pins 63a and 64a are associated with the coupling 51, and are supported in tubular guides 65a and 66a, respectively, of the tubing head 10.

Since the four alignment and support pins 63, 64, 63a and 64a are identical in structure, as are the four guides 65, 66, 65a and 66a, only the pin 63 and the guide 65 associated therewith Will be here described in detail.

The pin 63 has an'outer non-circular end or head 71 adapted to receive a suitable tool (not shown) for imparting rotary movement thereto. At its inner end 72, the pin 63 is tapered to fit into the notch 61 of the flange 53. A short distance outward from the tapered end 72,, the pin 63 is externally threaded at 73. The inner end of the tubular guide 65 is threaded into a radially extending socket 67 in the tubing head 16 where it preferably is welded to permanently secure the guide 65 in proper position. The socket 67 extends through a side wall of the tubing head, so that the pin 63, which is mounted in the bore 74 of the guide 65, can project into the vertical bore 13 of the tubing head It) at such a position intermediate the upper and lower ends thereof that its longitudinal axis is slightly above the horizontal plane occupied by the lower end of the hanger coupling 56 when the coupling is in the desired tubing-suspending position.

As an optional arrangement, the tubular guides 65, 66, 65a and 66a for the pins 63, 64, 63a and 64a, respectively, can be formed as integral parts of the tubing head 10.

The bore 74 of the guide 65 is threaded along part of its length, as indicated at 75. A counterbore 76 at the outer end of the guide 65 provides a shoulder 77, against which a seal-retaining washer 7S rests. A packing ring 79 is held in position against the washer 78 by a gland nut 80. The outer end 31 of the counterbore 76 is tapped to receive the nut 80 so that the latter can be turned to energize the packing 79. It will be apparent that when the head 71 of the pin 63 is rotated, said pin, being slidable within the washer 78, packing ring 79 and nut 86, can be projected into the notch 61, or retracted therefrom, as desired. An outwardly facing annular shoulder 68 in the bore 74 of the guide 65 is engaged by an inwardly facing annular shoulder 69 on the pin 63 when the pin has been screwed into the guide to that position wherein its inner end is projected the proper distance into the bore 13 of the tubing head as will be explained more fully hereinbelow.

The tubing strings, as Well as the couplings 50 and 51 and seal assembly of the invention are installed while a conventional blowout preventer (not shown) is in position upon the upper flange 12 of the tubing head and one or more packers (not shown) are in position in a lower part of the well. As the tubing string 57 is run, the hanger coupling 50 is attached to the uppermost tubing joint of the string and a back pressure valve (not shown) is inserted into the hanger coupling 50, as hereinabove mentioned. The tubing string and hanger assembly is then lowered through the blowout preventer and tubing head 10 into the well casing until the lower end of the tubing string engages a packer, this being made possible by the fact that the maximum transverse dimension of the hanger coupling 50 is less than the minimum diameter of the bore 13, of the tubing head 10. The hanger coupling 50 is then raised until the lower end of the coupling 56 is slightly above the level of the support pins 63 and 64 (the latter being in retracted position). Thus, the entire tubing string 57 is placed in tension, with the lower end of the string 57 secured to a packer. The pins 63 and 64 are then screwed in as far as possible, as determined by engagement of their shoulders 69 with the shoulders 68 of their guides 65 and 66, respectively. This will cause the inner ends 72 of the pins to project into the bore 13 of the tubing head 10 just far enough to assure proper positioning of the hanger coupling 50 within the tubing head 10. The hanger coupling is then lowered, and unless the notches 61 and 62 are already in alignment with the pins 63 and 64, respectively, the coupling is turned so as to attain such alignment, so that the cou pling can be lowered far enough to seat the conical inner ends of the pins 63 and 64 within the notches 61 and 62. The pins locate the hanger accurately in its operative position as regards to its height within the head 10, its lateral position therein, and its position of rotation about a vertical axis. Furthermore, the pins 63 and 64 then firmly support the hanger 50 and the string of tubing 57 suspended therefrom, so that the installation tool (not shown) can then be removed from its engagement with the threads 58 at the upper end of the coupling 50.

The string of tubing 57a associated with the hanger coupling 51 is then run in the same manner, the hanger coupling 51 is attached to its upper end, and a back pressure valve (not shown) installed in the hanger coupling 51. The tubing string 57a and coupling 51 thus assembled are then lowered and manipulated in a manner to latch the lower end of the tubing string 57a to the same or another packer, and raised. The pins 63a and 64a are then run inward as far as possible, this being determined by engagement of their shoulders 69 with the shoulders 68 of the guides 65a and 66a, respectively. The tubing string 57a and hanger coupling are then lowered into place, i.e., until the pins 63a and 64a seat within the notches 61 and 62 of the hanger coupling 51 in supporting and locating relation therewith.

The sealing assembly 16 then should be inserted through the blowout preventer and installed in position encircling both hanger couplings 5t} and 51, and locked into position by means of four pins 82, 33, 84 and 85 (FIG. 4) which are movably mounted in bores 86, S7, 88 and 89, respectively, extending radially from the counterbore 14 of the tubing head til to the exterior thereof with the axes of the bores in the horizontal plane occupied by the upper surface of the top plate 17 of the sealing assembly 16 when the latter is in its operative position. Inasmuch as the pins 82, 83, 84 and 85 are of identical structure, as are the bores 86, 87, 88 and 89, only the pin 82, the bore 86, and the elements associated therewith will be described in detail.

The pin 82 is tapered at its inner end 90, and is threaded over a part of its length adjacent thereto, as shown at 91. The outer end of the pin is formed with a head 92 adapted to receive a tool for rotation thereof. The radial bore 86 is threaded adjacent its inner end at 93, and is enlarged at 94 to receive a washer 95 and a packing ring 96. The enlarged bore portion 94 is tapped at its outer end for reception of a gland nut 97. It will be apparent that, upon rotation of the head 92, the pin 82, being slidable within the washer 95, packing 96 and nut 97, will be moved inwardly or outwardly, depending upon the direction of rotation.

The upper plate 17 of the sealing assembly 16 is beveled along its upper circumferential edge, as shown at 98 (FIG. 1). When the sealing member 16 is inserted, the holddown pins 82, 83, 84 and 85 must be in a retracted position (not shown). When the sealing member is placed in its operative position, the pins 82, 83, 84 and 85 should be turned to project them inwardly into the positions shown in FIG. 4, in which their inner tapered ends engage the beveled upper edge 98. This not only locks the sealing assembly 16 in place, but it also energizes the seal by so squeezing the packing element 19 between the metal plates 17 and 18 that the packing element is expanded radially into tight, fluid sealing relation with the counterbore 14 of the tubing head 10 and with the outer surfaces of the hanger couplings 50 and 51.

The two back pressure valves (not shown) in the hanger couplings 50 and 51 prevent upward flow through the tubing strings 57 and 57a, respectively. The well is thus kept under complete control, permitting safe removal of the blowout preventer and substitution therefor of a christmas tree 32, which should have two independent bores 33 and 34 having counterbores 33 and 34, respectively, to accommodate the upper ends of the hanger couplings 50 and 51, respectively, since the latter project upward beyond the upper surface of the tubing head 10, as shown in FIG. 1. The hereinbefore mentioned 0- ring seal 60 prevents leakage between the hangers 50, 51 and the Christmas tree 32.

In the modification of the invention shown in FIGS. 5-9 a tubing hanger assembly is illustrated comprising a tubing head 110, a sealing assembly 116, and Christmas tree 130, all of which elements are identical in both structure and function to the corresponding elements of the assembly illustrated in FIGS. 1-4.

These elements will therefore not here be specifically described. However, the modification of FIGS. 5-9 includes hanger couplings 150 and 151, hanger alignment and support members 163, 164, 167 and 168 and tubular guides 165, 166, 169 and 170 therefor which are of 5 modified construction as compared with their counterparts in the first described form of the invention. Therefore, detailed descriptions of these elements will be here included. Since the four said alignment and support members are identical with each other, as are the four said tubular guides, only the member 167 and the guide 169 will be here described in detail.

Referring particularly to FIG. 6, it will be seen that the alignment and support member 167 includes a pin 171 having at its outer end a head portion 171' enabling the pin 171 to be rotated by a suitable tool (not shown). The pin 171 is adapted when rotated to cause a supporting element 172 engaged by the inner end of the pin 171 to move radially of the tubing head 110. The pin 171 is threaded along a substantial portion of its length adjacent its inner end, as indicated at 173. The supporting element 172 is slidable within the bore 174 of the tubular guide 169 and projects therefrom into the vertical bore 113 of the tubing head 1101 The threaded inner end 173 of the pin 171 is engaged'in a tapped hole 175 in the outer end of the element 172.

' The tubular guide 169 has a counterbore 176 at its outer end, and the internal shoulder 177 thus formed provides an abutment for a flange 178 of the pin 171. A packing annulus 179 and a gland nut 180 screwed into the outer end of the counterbore 176, tapped as shown at 181, hold the flange 178 against the shoulder 177 and there-fore not only prevent axial movement of the pin 171 but also prevent leakage through the bore 174 of the guide 169. 35

The supporting element 172 is provided at one side with a longitudinally extending keyway 190 which slidably receives a key 191 projecting from the wall of the bore 174. The keyway 190 extends from the inner end of the supporting element 172 to a point short of its outer end, and thus leaves a shoulder 192 adjacent said outer end. It will thus be seen that when the pin 171 is rotated it remains in place while the supporting element 172 is moved radially inwardly or outwardly (depending upon the direction of rotation of the pin) between the inner position shown in FIG. 6, in which the shoulder 192 abuts the key, and the outer position in which the threaded portion 173 of the pin 171 is at its deepest possible position within the threaded bore 175. At the same time, the element 172 is prevented from rotating by the key 191 within the keyway 190.

7 As seen in FIG.-7, the hanger couplings 150 and 151 are cylindrical throughout their length. Special means are provided for seating the couplings 150 and 151 so as to prevent possible disengagement thereof from the supporting members 172 after being landed thereon. For this purpose, each of the hanger couplings is formed at its lower end with a bead 193 of V-shaped cross section and projecting downward through the entire circumference of the lower end of the coupling.

= Each of the support elements 172 is cylindrical except at its inner end 185, which is concavely curved through approximately 90 and about a vertical axis oifset laterally from the horizontal, longitudinal axis of the support element, as best shown in FIG. 8. The curvature of this concavely curved end 185 is such that it substantially conforms to the cylindrical outer surface of the associated hanger coupling. An arcuate, horizontal ledge 194 projects from the concave end 185 of the support 70 element 172. The ledge 194 terminates in a concave, vertical surface 186 that conforms to the outer cylindrical surface of the tubing string 157 or 157 connected to the hanger coupling 150 or 151, as the case might be. Formed in the upper surface of the ledge 194 is a groove 75 6 195 of V-shaped cross section and curved to conform to the bead 193 of the associated hanger coupling throughout approximately one quarter of the extent of the latter.

The hanger structure of FIGS. 5-9 is operated in a similar manner as that of FIGS. 1 to 4. When seated, the hangers 154) and 151 rest upon the ledges 194, with the beads 193 inserted in the grooves 195 of the support elements 172.

FIGS. 10 and 11 illustrate another modified form of the tubing hanger assembly of this invention, wherein two tubing hanger couplings 25b and 251 (FIG. 11) resemble the hanger couplings 5t and 51 of the first above described form to the extent that each hanger coupling 251i, 251 comprises an upper cylindrical part 252 and a semicylindrical part 253 resembling a flange projecting radially therefrom adjacent the lower end thereof. However, each of the hanger couplings 250 and 251 is a two-part structure, the semi-cylindrical lower part 253 being made separately from the upper, cylindrical part 252 and being mounted thereon in such a manner that the two parts are rotatable with respect to each other. For this purpose, the bore 392 of the semi-cylindrical part 253 is formed at its upper end with a counterbore 304 which is dimensioned to receive therein the lower end of the upper, cylindrical part 252. The two parts are rotatably interconnected and prevented from moving axially with respect to each other by a series of ball bearings 3% (FIG. 10) disposed within registering annular grooves 3457 and 308 in' the outer surface of the upper part 252 and in the counterbore 304 of the lower part 253, respectively. After the parts 252 and 253 are assembled, the balls 3% are inserted into the grooves 397, 3% through one or more access openings 399 extending from the groove 3% to the outer surface of the lower part 253. After the balls 386 are inserted, a ball retainer plug 311 is screwed into each or" the access openings 369.

The bores 3%2 of the semi-cylindrical parts 253 of the two hanger couplings 25d and 251 are of sufficiently large diameter to provide clearance for the upper ends of the tubing strings 257 and 257a that are to be supported by the couplings 250 and 251, respectively. The bore 254 of each upper coupling part 252 is provided at its lower end with female threads 255 adapted to receive male threads 256 at the upper end of the respective tubing string 257 or 257a. Thus, each tubing string 257, 257a is suspended in a manner permitting free rotation thereof, while the lower, semi-cylindrical parts 253 of the two hanger couplings are each mounted in fixed relation to the tubing head 210 at the top of the casing (not shown) within which the tubing strings 257 and 257a are arranged.

The weight of hanger coupling 250 and the tubing string 257 suspended therefrom is transmitted to the tubing head 216 by a pair of pins 263 and 264, which differ from the corresponding pins 63, 64 and 163, 164 of the previously described forms of the invention in that the pins 263 and 264, instead of being arranged radially with respect to the tubing head 210, are disposed opposite and in axial alignment With each other in a vertical plane that is offset from the vertical axis of the tubing head 21%, as clearly shown in FIG. 11.

The pins 263 and 264 are mounted in guides 265 and 266, respectively, which in this instance are integral with the tubing head 21% and project from the outer surface thereof in such alignment with each other that the above described relative positioning of the pins 263 and 264 is attained. As in the case of the first above described form of the invention, each pin 263, 264 is provided with a seal ring 279 and is threaded through a gland nut 280 that presses a seal ring retaining washer 278 against a shoulder 277"formed within the bore of the associated guide 265 or 266 to energize the seal 279. The frusto-conical inner ends 272 of the pins 253 and 264 project into the bore 213 of the tubing head 21%) and seat Within complementary sockets or notches 261 and 262, respectively, in the outer, arcuate surface of the lower part 253 of the hanger coupling 250. These notches 261 and 262 open not only outward, but also downward at the bottom end surface of the part 253, so that after the tubing string 257 has been connected to the packer and the hanger coupling 25-9 returned to an elevation above that of the pins 263 and 264, as already explained, the pins 263 and 264 can then be run into their final, operating positions; i.e., until annular shoulders 269 thereon engage, opposed shoulders 268 that are formed in the bores of the pin guides 265 and 266. The hanger coupling 250 and the tubing string 25. thereof can then be lowered into their operative position while the pins 263 and 264 project into the bore 213. While this is being carried out, the pins enter the notches and thus serve as locators to guide the coupling into its final position and prevent it from being lowered thcrepast. Thereafter, the pins 263 and 264 immobilize the lower part 253 of the coupling 250 within the tubing head 210 and dependably retain the upper part 252 of the coupling at fixed elevation therein although the above described antifriction means interconnecting the parts 252 and 253 permits the upper part 252 and the tubing string 257 suspended therefrom to rotate freely.

The other hanger coupling 251 is similarly mounted in the tubing head 210 by pins 263a and 264a which locate and support the coupling 251 adjacent and in parallel relation to the hanger coupling 2"0, so that the tubing string 257a, likewise, is suspended at fixed vertical position within the well casing but in a manner permitting free and independent rotation of the string 257a.

As in the cases of the forms of the invention illustrated, respectively, in FIGS. 1 and 5, a sandwich type of seal assembly 216 is provided to maintain a fluid-tight seal between the two couplings 250 and 251 and the tubing head 210. The seal assembly 216 comprises rigid upper and lower plates 217 and 218, respectively, and an intermediate packing element 219 that is energized when four pins 282, two of which are shown in FIG. 10, are tightened. The arrangement and manner of operation of the four pins 282 are similar to the arrangement and operation of the four seal assembly energizing pins 82, 83, 84 and 85 shown in FIG. 4.

The hanger structure of FIGS. 10 and 11 is operated similarly to each of the previously described forms of the invention. Since the maximum diameter of each of the tubing hanger couplings is less than the minimum diameter of the bore 213 of the tubing head 210, either coupling 250 or 251 can pass freely through the tubing head 210 to effect engagement of the tubing string supported thereby with a packer (not shown) previously installed in the well, regardless of whether the companion tubing hanger and tubing string has previously been installed. The hanger structure of FIGS. 10 and 11 is possessed of the additional advantage that each of the two tubing strings 257 and 257a suspended therefrom is freely rotatable with respect to the tubing head by which it is supported and to the well casing within which the two strings are disposed in side-by-side arrangement. Furthermore, each string 257, 257a is rotatable independently of the other, which fact makes it possible to use the hanger assembly of FIGS. 10 and 11 in conjunction with packers that require rotation of a tubing string in order to effect engagement thereof with one of the packers.

It will be understood that modifications and variations of the invention disclosed herein may be made without departing from the scope of the invention.

Having thus described the invention, what is claimed as new and is desired to be protected by Letters Patent is:

1. Apparatus for suspending two strings of tubing within a well, comprising a tubing head having a bore therethrough, two tubing hanger couplings receivable side-by-side within the bore of said tubing head, each of said couplings including a semi-cylindrical flange and tubular portion projecting therefrom and rotatably connected thereto, each of said tubing strings being connectcd to the tubular portion of one of said couplings, the flanges of said two hanger couplings being arranged with their flat surfaces in face-to-face relation, and independent supporting means for each of said hanger couplings mounted on said tubing head, each of said supporting means being movable between an operative position projecting into the tubing head bore under the flange of the associated coupling to support the coupling and an inoperative position removed from the tubing head bore to allow passage of the associated coupling through the tubing head bore.

2. Apparatus for rotatably supporting two strings of tubing in side-by-side relation within a well, comprising a tubing head having a bore therethrough, two tubing hanger couplings receivable within said bore independently of each other, each of said hanger couplings including two separate parts, one of said parts being a semi-circular flange and the other being a tubular member projecting from said flange, means interconnecting said parts for rotary motion and preventing axial motion relative to each other, releasable means independently associated with each of said hanger couplings for rigidly connecting said semi-circular flange to the tubing head to be supported thereby, and means for connecting a tubing string to each of said tubular parts of said two hanger couplings to rotatably support the two tubing strings upon the tubing head for independent rotary mo-- tion, the maximum transverse dimension of the semicircular flange of each of said tubing hanger couplings being less than the minimum diameter of the bore of the tubing head to provide for free passage of either tubing hanger coupling through the tubing head when the associated releasable means is released.

References Cited in the file of this patent UNITED STATES PATENTS 1,529,605 Owen Mar. 10, 1925 1,595,310 Mueller et al. Aug. 10, 1926 1,938,062 Brown Dec. 5, 1933 2,159,401 Rector May 23, 1939 2,237,683 Minor -2. Apr. 8, 1941 2,254,752 Penick Sept. 2, 1941 2,507,246 Davidson et al. May 9, 1950 2,599,039 Baker June 3, 1952 2,754,134 Watts July 10, 1956 2,768,841 Allen Oct. 30, 1956 2,794,505 Allen June 4, 1957 2,830,665 Burns Apr. 15, 1958 2,927,804 Snyder Mar. 8, 1960- 2,930,633 Ethington Mar. 29, 1960 2,934,148 Allaire Apr. 26, 1960 FOREIGN PATENTS 456,875 Great Britain Nov. 17, 1936 

1. APPARATUS FOR SUSPENDING TWO STRINGS OF TUBING WITHIN A WELL, COMPRISING A TUBING HEAD HAVING A BORE THERETHROUGH, TWO TUBING HANGER COUPLINGS RECEIVABLE SIDE-BY-SIDE WITHIN THE BORE OF SAID TUBING HEAD, EACH OF SAID COUPLINGS INCLUDING A SEMI-CYLINDRICAL FLANGE AND TUBULAR PORTION PROJECTING THEREFROM AND ROTATABLY CONNECTED THERETO, EACH OF SAID TUBING STRINGS BEING CONNECTED TO THE TUBULAR PORTION OF ONE OF SAID COUPLINGS, THE FLANGES OF SAID TWO HANGER COUPLINGS BEING ARRANGED WITH THEIR FLAT SURFACES IN FACE-TO-FACE RELATION, AND INDEPENDENT SUPPORTING MEANS FOR EACH OF SAID HANGER COUPLINGS MOUNTED ON SAID TUBING HEAD, EACH OF SAID SUPPORTING MEANS BEING MOVABLE BETWEEN AN OPERATIVE POSITION PROJECTING INTO THE TUBING HEAD BORE UNDER THE FLANGE OF THE ASSOCIATED COUPLING TO SUPPORT THE COUPLING AND AN INOPERATIVE POSITION REMOVED FROM THE TUBING HEAD BORE TO ALLOW PASSAGE OF THE ASSOCIATED COUPLING THROUGH THE TUBING HEAD BORE. 